Abstract: Measured motion discrimination (using a dynamic random dot display) in
     95 visually normal Subjects (aged 25-80 yrs) to determine whether motion
     sensitivity deteriorates with age. Motion thresholds were found to increase
     linearly with age and double between 25 and 80 yrs of age. This increase
     was not attributable to pupil size or optical blur but most likely resulted
     from age-related neurodegeneration in the retinocortical pathway.
     Subsequently, the motion sensitivity of 20 patients (aged 62-82 yrs) with
     senile dementia of the Alzheimer type (SDAT) was compared with results from
     a subset of similarly aged visual normals. In SDAT Subjects there were
     significant threshold elevations, which were more pronounced in Subjects
     with more severe dementia. Findings support the suggestion that significant
     loss occurs in SDAT as well as in normal aging. Motion threshold may reveal
     preclinical damage to the primary visual pathways in early SDAT. ((c) 1997
     APA/PsycINFO, all rights reserved).